Question

Crossing-over occurs

a. during prophase 2.
c. during prophase I.
b. during fertilization.
d. at the centromere

Answer 1

C. Prophase 1 crossing over occurs during prophase 1 of meiosis.

Answer 2

Answer : prophase I

Internets prove: Crossing over occurs only during prophase I.
The complex that temporarily forms between homologous chromosomes is only present in prophase I, making this the only opportunity the cell has to move DNA segments between the homologous pair.